An Electrochemical Study on the Effect of Salt Affecting to Corrosion Behavior of Concrete Reinforced Steel in Natural Sea Water

J. Ocean Eng. Technol. 2000;14(4):23-29.

천연해수에 침지된 콘크리트 내부의 철근부식거동에 미치는 염분의 영향에 관한 전기화학적 연구

김광근,류보현,점성종,김기준,문경만

한국해양대학교 부식방식공학 연구소,한국해양대학교 부식방식공학 연구소,한국해양대학교 부식방식공학 연구소,한국해양대학교 부식방식공학 연구소,한국해양대학교 부식방식공학 연구소

Keywords: Chloride ion, Corrosion potential, Friedel salts, Corrosion inhibitor

핵심용어: 염소이온, 부식전위, 프리델씨 염, 부식억제제

Abstract

When the concrete structures were being made with sand containing chloride ion it was knows that corrosion rate of reinforced steel embedded in concrete with chloride ion was higher than that of concrete with on chloride ion. In this study, the operation of Friedel salts affecting the corrosion behavior of reinforced steel embedded in cement mortar was investigated with electrochemical view. Corrosion potential of reinforced steel embedded in cement mortar with sand containing chloride ion was shifted noble direction than that of cement mortar with no chloride ion after immersed 5 month in natural sea water and also corrosion current density decreased with shifting corrosion potential to noble direction. However Friedel salts appeared from surface to 2.5cm of inside direction of mortar specimen, which is located at 11.5$circ$(2$ heta$) in XRD analysis and the amount of Ca(OH)2 by SEM photograph in cement mortar with chloride ion was larger than that of cement mortar with mo chloride ion. Eventually it is suggested that Friedel salts was resulted from chloride ion and it acted as the corrosion inhibitor